Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/087—Binders for toner particles
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
  • G03G9/00—Developers
  • G03G9/08—Developers with toner particles
  • G03G9/087—Binders for toner particles
  • G03G9/08742—Binders for toner particles comprising macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
  • G03G9/08755—Polyesters
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/42—Polycondensates having carboxylic or carbonic ester groups in the main chain
  • C08G18/4202—Two or more polyesters of different physical or chemical nature
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/02—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds
  • C08G63/12—Polyesters derived from hydroxycarboxylic acids or from polycarboxylic acids and polyhydroxy compounds derived from polycarboxylic acids and polyhydroxy compounds
  • C08G63/16—Dicarboxylic acids and dihydroxy compounds
  • C08G63/20—Polyesters having been prepared in the presence of compounds having one reactive group or more than two reactive groups
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/001—Electric or magnetic imagery, e.g., xerography, electrography, magnetography, etc. Process, composition, or product
  • Y10S430/104—One component toner

Definitions

• the present invention relates to a binder resin for a toner and a toner and in particular to a binder resin for a toner and a toner comprising a specific polyester resin. Also, the invention relates to a binder resin for a toner and a toner, used for electrophotography.
• thermophotography-based copying machines and printers With the progress of office automation, the demand for electrophotography-based copying machines and printers has increased rapidly and performance requirements for such equipment have become higher.
• a generally used method which comprises forming an electrostatic latent image on the photo-sensitive material, then developing the image using a toner, transferring the toner image onto a fixing sheet such paper or the like, and heat-pressing the transferred toner image using heat roll (a hot roll fixing method).
• a hot roll fixing method in order to achieve enhanced economical efficiency in power consumption and increased photography speed, and to prevent papers from being curled, a toner superior in fixing properties is needed, which can be fixed at a lower temperature.
• a toner using a polyester resin owing to higher density for a binder resin is often proposed, replacing the conventional styrene-acrylic resin.
• styrene-acrylic resin e.g. publications of JP61-284771A, JP62-291668A JP07-101318B and JP08-3663B, and specification of U.S. Pat. No. 4,833,057, etc.
• main components are a bisphenol-A type derivative and terephthalic acid.
• a toner (JP08-5947B) using a polyester resin having large number of terephthalic acid and ethylene glycol or 1,4-butanediol derived units is proposed.
• the resulting toner does not solve the above problems.
• PET polyethyleneterephthalate
• An object of the present invention is to solve problems caused by the conventional toners and also to provide a binder resin for a toner and a toner superior in low-temperature fixing properties, offset resistance and development durability even when copying for a long period.
• the present invention has been realized as a result of extensive review. That is, the present invention is specified by the matters described in the following (1) to (6).
• a binder resin for a toner comprising a polyester resin, wherein the polyester resin comprises 0.1 to 40% by weight of tetrahydrofuran insoluble component (A-1) and 99.9 to 60% by weight of tetrahydrofuran soluble component (A-2),
• a binder resin for a toner used in the present invention comprises a polyester resin (A).
• the polyester resin (A) comprises 0.1 to 40% by weight of a tetrahydrofuran (THF) insoluble component (A-1) and 99.9 to 60% by weight of a tetrahydrofuran soluble component (A-2).
• the tetrahydrofuran insoluble component (A-1) is 0.5 to 25% by weight and the tetrahydrofuran soluble component (A-2) is 99.5 to 75% by weight.
• the tetrahydrofuran insoluble component (A-1) is less than 0.1% by weight, an offset resistance is not sufficient in some cases.
• the tetrahydrofuran insoluble component is more than 40% by weight, the fixing properties are deteriorated in some cases.
• the tetrahydrofuran insoluble component (A-1) of the polyester resin (A) according to this invention is first described in detail.
• the tetrahydrofuran insoluble component (A-1) of the polyester resin (A) according to the invention comprises a terephthalic acid-derived structure unit (I), a particular polyhydric alcohol-derived structure unit (II) and an atomic group structure unit (III) selected from C, H, N, O and S.
• the tetrahydrofuran insoluble component (A-1) seems to be insoluble even in such a good solvent as a tetrahydrofuran because of its crosslinked structure.
• the polyhydric alcohol-derived structure unit (II) comprises
• dihydric alcohol-derived structure unit (II-1-1) having 2 to 10 carbon atoms there can be mentioned, for example, dihydric alcohol-derived structure units such as ethylene glycol, 1,2-butanediol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, triethylene glycol, dipropylene glycol, 1,5-pentanediol, 1,6-hexanediol, neopentylglycol, 2-ethyl-1,3-hexanediol, etc.
• dihydric alcohol-derived structure units such as ethylene glycol, 1,2-butanediol, 1,2-propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanedi
• Ethylene glycol, diethylene glycol and triethylene glycol-derived structure units are preferred. Ethylene glycol-derived structure unit is preferred particularly. Because diethylene glycol and triethylene glycol-derived structure units can lower the glass transition temperature (Tg) as compared to the ethylene glycol-derived structure unit, they are used preferably in order to control Tg.
• Tg glass transition temperature
• the trihydric alcohol-derived structure unit (II-1-2) having 3 to 10 carbon atoms there can be mentioned, for example, trihydric alcohol-derived structure units such as trimethylolpropane, glycerin, 2-methylpropanetriol, trimethylolethane or the like. The trimethylolpropane-derived structure unit is particularly preferred.
• the proportion of the dihydric alcohol-derived structure unit (II-1-1) having 2 to 10 carbon atoms is preferably 45 to 75 mole % and more preferably 45 to 71 mole %.
• the proportion is less than 39.9 mole %, a lower density and inferior mechanical durability result in some cases.
• the proportion is more than 75 mole %, a higher density, inferior grindability and lower productivity result in some cases.
• the proportion of the trihydric alcohol-derived structure unit (II-1-2) having 3 to 10 carbon atoms is preferably 2 to 18 mole % and more preferably 3 to 14 mole %.
• the proportion is less than 0.1 mole %, it is difficult to crosslink as described below, and accordingly the high molecular weight component decreases. Therefore, an offset resistance or mechanical durability could be deteriorated in some cases.
• the proportion is more than 20 mole %, excessive crosslinkage occurs so that the molecular weight becomes excessively higher, and accordingly grindability is deteriorated. Or a rapid gelation takes place when a high molecular polymer is produced by polyester polycondensation as described later, making it difficult to control an intended reaction in some cases.
• dihydric alcohol-derived structure unit containing bisphenol skeleton (II-2) there are mentioned, for example, bisphenol A type derivative-derived structure units such as a bisphenol A-polyethylene oxide adduct used for desirable examples besides a bisphenol A-2 propylene oxide adduct or bisphenol A-3 propylene oxide adduct.
• bisphenol A type derivative-derived structure units such as a bisphenol A-polyethylene oxide adduct used for desirable examples besides a bisphenol A-2 propylene oxide adduct or bisphenol A-3 propylene oxide adduct.
• an alkylene oxide adduct it is necessary that the carbon atoms in the alkylene are 2 to 10 and that the number of addition is 2 to 20.
• the proportion of the dihydric alcohol-derived structure unit containing bisphenol skeleton (II-2) is preferably 15 to 45 mole % and more preferably 15 to 30 mole %.
• the proportion is less than 15 mole %, a density gets excessively high, and accordingly grindability is deteriorated so that productivity is lowered in some cases. And inferior mechanical durability results in some cases.
• the proportion is more than 60 mole %, a density is excessively lowered and the mechanical durability is worsened in some cases.
• An atomic group structure unit (III) having one or more kinds of elements selected from C, H, N, O and S is contained in an amount of 0.1 to 30 mol % based on the total moles of all the polyhydric alcohol-derived structure units in component (A-1).
• the atomic group structure unit (III) subjects mainly a resin comprising a terephthalic acid-derived structure unit (I) and a polyhydric alcohol-derived structure unit (II) to crosslinkage and high molecular weight.
• diisocyanate-derived structure unit such as hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate, etc. or an isocyanate-derived structure unit such as a tri- or higher polyisocyanate, etc. besides tolylene diisocyanate.
• a tolylene diisocyanate-derived structure unit is particularly preferred.
• the isocyanate-derived structure unit is used preferably owing to its high inter-molecular binding force and accordingly excellent mechanical durability results.
• the proportion of the atomic group structure unit (III) is preferably 1 to 15 mole % and more preferably 1 to 10 mole %.
• the proportion is less than 0.1 mole %, a crosslinking portion is small, which means that a high-molecular weight material component becomes small. Therefore, there are some cases where an offset resistance and the mechanical durability become deteriorated.
• the proportion is more than 30 mole %, inferior grindability results or it is difficult to control an intended reaction upon crosslinking reaction to be described later.
• the tetrahydrofuran insoluble component (A-1) structure can be analyzed and determined by analyzing carboxylic acids, alcohol, etc. resulted from thorough decomposition of the resin by means of hydrolysis reaction, using chromatography, IR, NMR or the like.
• the tetrahydrofuran soluble component (A-2) is elaborated as follows.
• the tetrahydrofuran soluble component (A-2) comprises a terephthalic acid-derived structure unit (I), polyhydric alcohol-derived structure units (IV) and (V), and a di- or higher functional atomic group structure unit (VI) having 1 to 20 carbon atoms.
• the polyhydric alcohol-derived structure unit (IV) comprises
• dihydric alcohol-derived structure unit (IV-1) having 2 to 10 carbon atoms there can be mentioned, for example, the same as the dihydric alcohol-derived structure unit (II-1-1).
• the ethylene glycol-derived structure unit is particularly preferred.
• dihydric alcohol-derived structure unit containing bisphenol skeleton (IV-2) there are specially mentioned, for example, a bisphenol A type derivative-derived structure unit which is identical to the dihydric alcohol-derived structure unit containing bisphenol skeleton (II-2) as described above.
• the proportion of the dihydric alcohol-derived structure unit (IV-1) having 2 to 10 carbon atoms is preferably 45 to 80 mole % and more preferably 50 to 75 mole %.
• the proportion is less than 40 mole %, density becomes lower so that the inferior mechanical durability results in some cases.
• the proportion is more than 85 mole %, density becomes higher so that deteriorated grindability and inferior productivity result in some cases.
• the proportion of the dihydric alcohol-derived structure unit containing bisphenol skeleton (IV-2) is preferably 15 to 45 mole % and more preferably 15 to 35 mole %.
• the proportion is less than 15 mole %, density becomes higher so that inferior grindability or a lower productivity result.
• density becomes lower so that inferior mechanical durability results.
• the tri- or higher functional atomic group structure unit (V) having one or more kinds of elements selected from C, H and O comprises 2 to 20 mole % based on the total moles of all the polyhydric alcohol-derived structure units in component (A-2).
• the tetrahydrofuran soluble component (A-2) has a branched structure so that orientation or crystallization is suppressed.
• the tri- or higher atomic group structure unit (V) there are mentioned, for example, the same structure units as the trihydric alcohol-derived structure unit (II-1-2) as specifically described above, more preferably a trimethylolpropane-derived structure unit.
• a polycarboxylic acid-derived structure unit such as a unit derived from trimellitic acid or pyromellitic or the like.
• the proportion of the tri- or higher functional atomic group structure unit (V) is preferably 2 to 15 mole %, and more preferably 2.5 to 10 mole %.
• the proportion is less than 2 mole %, orientation and crystallization of molecular chains appear while melting so that inferior fixing properties result in some cases.
• the proportion is more than 20 mole %, a rapid gelation takes place when a high molecular polymer is produced by polyester polycondensation or the like to be described later, making it difficult to control an intended reaction in some cases therefore, such a proportion is not preferred.
• the proportion of the bi- or higher functional atomic group structure unit (VI) having 1 to 20 carbon atoms is 0 to 10 mole %, based on 100 mole % of the total moles of all the polyhydric alcohol-derived structure units in component (A-2).
• the atomic group structure unit (VI) mainly crosslinks low-molecular weight polyester resins to have the effects of a reduced low-molecular weight component which results in inferior offset resistance.
• atomic group structure unit (VI) there are mentioned in concrete terms, for example, compound-derived structure units such as tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylene diisocyanate and the like. Particularly preferred is the tolylene diisocyanate-derived structure unit.
• the proportion of the atomic group structure unit (VI) is preferably 0.1 to 10 mole %, and more preferably 1 to 10 mole %. When the proportion exceeds 10 mole %, the high molecular weight component gets excessively increased so that the fixing properties are inferior in some cases.
• the tetrahydrofuran soluble component (A-2) has 6 to 100 for its Mw/Mn values preferably when measured by GPC, and more preferably 6 to 60.
• Mw/Mn is small, insufficient offset resistance results; when it is great, the fixing properties are deteriorated in some cases.
• the tetrahydrofuran soluble component (A-2) structure can be analyzed and obtained by analyzing the tetrahydrofuran solution portion (A-2) itself, using IR, NMR or the like in the same method as the tetrahydrofuran insoluble component (A-1).
• a binder resin for a toner used in the present invention has a peak molecular weight of 3,000 to 18,000 when measured by GPC.
• the peak molecular weight is less than 3,000, deteriorated offset resistance and inferior mechanical durability result; when the peak molecular weight is more than 18,000, the fixing properties are deteriorated.
• the compound-derived structure unit by the present invention is comprised in the polyester resin (A), then its production process is not particularly restricted. That is, there is no need to use raw materials of the corresponding compounds and compounds other than the corresponding compounds can be used to produce the polyester resin (A); the resulting polyester resin once obtained can be used without any problem.
• the present invention is not particularly restricted to a process for producing the polyester resin (A), but preferably a method to obtain the polyester resin (A) can be mentioned by reacting the polyester resin (a-1) comprising
• the polyester resin (A) can be produced using the corresponding carboxylic acid, alcohol and isocyanate. Also, the corresponding terephthalic acid polyester resin can further be used. As preferable examples, processes are used for producing the terephthalic acid polyester resin (A) comprising the steps of:
• polyester resin (a-1) by depolymerization and polycondensation of
• polyester resin (a-2) by depolymerization and polycondensation of
• a terephthalic acid derivative (i) used in production of a polyester resin (a-1) and a polyester resin (a-2) there are mentioned, for example, a terephthalic acid, a terephthalic anhydride, alkyl esters of the terephthalic acid or the like.
• the terephthalic acid is preferred.
• aliphatic dicarboxylic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and the like
• unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, itaconic acid and the like
• aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, phthalic anhydride and the like
• anhydrides or lower alkyl esters of these dicarboxylic acids such as aliphatic dicarboxylic acids such as malonic acid, succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid, and the like
• unsaturated dicarboxylic acids such as maleic acid, fumaric acid, citraconic acid, itaconic acid and the like
• aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid,
• a monocarboxylic acid and a polycarboxylic acid for the purpose of molecular weight control.
• monocarboxylic acids there are mentioned aliphatic carboxylic acids such as octanoic acid, decanoic acid, dodecanoic acid, myristic acid, palmitic acid, stearic acid and the like, and they may have branches or unsaturated groups. These aliphatic monocarboxylic acids may be used for the purpose of control of glass transition temperature because of having an action of giving a reduced glass transition temperature.
• Aromatic carboxylic acids such as benzoic acid, naphthalenecarboxylic acid or the like may be used too.
• tri- or higher carboxylic acid there are mentioned, for example, trimellitic acid, pyromellitic acid and anhydrides thereof.
• dihydric alcohol (ii-1-1) having 2 to 10 carbon atoms and dihydric alcohol (iv-1) having 2 to 10 carbon atoms there can be mentioned the dihydric alcohol described before.
• dihydric alcohol described before.
• ethylene glycol or 1,4-butanediol used in production of polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) as described below.
• PET polyethylene terephthalate
• PBT polybutylene terephthalate
• Ethylene glycol is particularly preferred.
• the bisphenol or the derivative thereof (ii-2) and bisphenol or the derivative thereof (iv-2) there can be mentioned, for example, the bisphenol A type derivative mentioned before.
• trihydric alcohol (iii-1-2) having 3 to 10 carbon atoms a tri- or higher functional alcohol (iv-3) having 1 to 20 carbon atoms, there can be mentioned the trihydric alcohol described before.
• Trimethylolpropane is particularly preferred.
• Other alcohols can be used together besides alkylene diol, triol, etherified bisphenol.
• polyhydric alcohols conventionally used in production of polyester resins, for example, alicyclic diols such as cyclohexanedimethanol, hydrogenated bisphenol A and the like; derivatives of bisphenol F or bisphenol S, such as, alkylene oxide of bisphenol F or bisphenol S of ethylene oxide, propylene oxide or the like; aromatic diols of dicarboxylic acid lower alkyl esters such as bishydroxyethylterephthalic acid, bishydroxypropylterephthalic acid, bishydroxybutylterephthalic acid or the like; and tetrahydric or higher alcohols such as pentaerythritol, sorbitol, sorbitan and the like.
• Monohydric alcohols can also be used for molecular weight control.
• monohydric alcohols there can be mentioned aliphatic monohydric alcohols such as octanol, decanol, dodecanol, myristyl alcohol, palmityl alcohol, stearyl alcohol and the like. They may have branches and unsaturated groups.
• terephthalic acid polyester (vii) there can be mentioned PET and PBT described before.
• the molecular weight distribution, composition and production process of these PET and PBT and its shape when it is used are not restricted.
• These polyesters are obtained by processing recycled products into a flake form such as PET bottle or the like and have a weight-average molecular weight of about 30,000 to 90,000.
• the terephthalic acid polyester (vii) the carboxylic acid, alcohol by depolymerization and polycondensation or by polycondensation at 200 to 270° C., more preferably at 220 to 260° C.
• the depolymerization and polycondensation may be carried out at a time.
• a reaction temperature is low, the solubility of aromatic polyester such as PET or PBT, or acid component such as terephthalic acid or the like during depolymerization is lowered, and accordingly the reaction time becomes longer; therefore, a high reaction temperature is not preferred because it incurs decomposition of the raw materials.
• the depolymerization reaction and polycondensation reaction can be conducted by a known process such as solvent-free high-temperature polycondensation, solution polycondensation or the like in an inert gas such as nitrogen gas or the like.
• the proportions of the acid monomer and alcohol monomer used are generally 0.7 to 1.4, in terms of the molar ratio of the hydroxyl group of the latter to the carboxyl group of the former.
• the reaction is preferably processed rapidly by adding a catalyst thereto.
• a catalyst there can be mentioned a tin oxide, specifically dibutyl tin oxide; however, catalysts are not restricted to them.
• the amount of the catalyst used is preferably 0.01 to 1.00% by weight.
• the polyester resin (a-1) of the present invention is a material to form the tetrahydrofuran insoluble component (A-1) by reacting and crosslinking with isocyanate (iii) to be described later.
• the hydroxyl value of the polyester resin (a-1) is preferably 10 to 100 mgKOH/g and more preferably 25 to 90 mgKOH/g.
• the polyester resin (a-2) is hardly reacted with isocyanate (iii), which is a material to be a main component of the tetrahydrofuran soluble component.
• the hydroxyl value of the polyester resin (a-2) is preferably less than 20 mg-KOH/g and more preferably less than 10 mgKOH/g.
• the polyester resin (A) can be produced either by reacting the polyester resin (a-1), the polyester resin (a-2) and polyisocyanate, what is called urethanization reaction, or by reacting the polyester resin (a-1) and isocyanate (iii) to reaction, and then to mixing it with the polyester resin (a-2).
• isocyanate (iii) there can be mentioned, for example, tolylene diisocyanate and other diisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, xylene diisocyanate, tetramethylene diisocyanate and the like.
• a known method can be adopted for the reaction of the isocyanate and polyester resin. Specifically, it may be conducted with a stirrer-fed reactor or with twin screw kneading extruder. It is preferably a method giving rise to a reaction in an extruder and more preferably in a twin screw kneading extruder.
• the temperature of the reaction is preferably 150 to 200° C.
• the amount of the polyester resin (a-1) and the polyester resin (a-2) is 1 to 70 parts by weight for the polyester resin (a-1) and preferably 5 to 50 parts by weight, while it is 30 to 99 parts by weight for the polyester resin (a-2) and preferably 50 to 95 parts by weight.
• the amount of isocyanate (iii) is varied depending on the isocyanate type or the hydroxyl value of polyester resin (a-1), which cannot be specified collectively; however, 0.1 to 1.0 parts by weight is preferred. More specifically, isocyanate is preferably 0.2 to 2 mole and more preferably 0.5 to 1.5 mole for 1 mole equivalent of the hydroxyl group value of polyester resin (a-1).
• the polyester resin (A) can be used as the binder resin for a toner as it is, but it can further comprise a wax.
• a wax there can be mentioned polyolefin wax such as polyethylene wax, polypropylene wax or the like. The amount thereof is preferably within the scope of 0 to 10 parts by weight in the binder resin for a toner.
• polyolefin wax examples include, but not limited to, Hi-wax 800P, 400P, 200P, 100P, 720P, 420P, 320P, 405 MP, 320 MP, 4051E, 2203A, 1140H, NL800, NP055, NP105, NP505, NP805 and the like produced by Mitsui Chemicals, Inc.
• the polyester resin (a-1) and isocyanate (iii), and, if necessary, the polyester resin (a-2) are reacted in the presence of a wax to use the resulting resin as the binder resin for a toner. It is more preferred that the polyester resin (a-1), isocyanate (iii) and the polyester resin (a-2) are reacted in the presence of a wax to use the resulting resin as the binder resin for a toner.
• the binder resin for a toner can further be mixed with the polyester resin (a-2).
• the isocyanate (iii) is reacted with the polyester in the presence of a wax so that the toner to be described later has superior grindability and toner particles with a uniform weight-average particle diameter can be obtained.
• a desirable weight-average particle diameter is less than 10 micro-meters and preferably 3 to 10 micro-meters and more preferably 5 to 10 micro-meters.
• a weight-average particle diameter of the toner can be measured, for example, with a coulter counter. When the weight-average particle diameter is more than 10 micro-meters, it is difficult to achieve fine images.
• the binder resin for a toner of the present invention other than waxes
• the conventional binder resin for a toner such as styrene copolymers, polyol resin, polyamide resin, silicone resin or the like.
• a density of the binder resin for a toner used in the present invention is preferably 1.20 to 1.27 g/cm 3 .
• the density is less than 1.20 g/cm 3 , the mechanical durability is worsened, while when the density is more than 1.27 g/cm 3 , the grindability is worsened; therefore the productivity is lowered.
• the polyester resin (A) used in the binder resin for the toner of the present invention has a glass transition temperature (Tg) of 40 to 70° C. preferably.
• Tg glass transition temperature
• the resulting toner causes agglomeration of toner particles, which is called blocking, while when Tg is extremely high, the fixing properties are worsened in some cases.
• the toner of the present invention is described in more detail below.
• the toner of the present invention comprises at least the binder resin for a toner of the present invention described before, charge control agent (CCA), colorants and surface-treating agent.
• CCA charge control agent
• the amount of binder resin for a toner of the present invention is preferably 50 to 90% by weight in the toner.
• the toner used in the present invention has such as a viscoelasticity that, in the curve obtained by using the axis of abscissas as temperature and the axis of ordinates as a logarithm G′ (storage modulus), it is needed that the maximum value and/or shoulder should not appear in the range 100 ⁇ 180° C. When the maximum value and/or shoulder appear in the curve, the fixing properties are worsened in some cases.
• colorants include, for example, carbon black, magnetite, Phthalocyanine Blue, Peacock blue, Permanent red, lake red, Rhodamine lake, Hansa Yellow, Permanent yellow, benzidine yellow, nigrosine dyes (C. I. No. 50415), aniline blue (C. I. No. 50405), charcoal blue (C. I. No. azoec Blue 3), chrome yellow (C. I. No. 14090), ultra marine blue (C. I. No. 77103), Dupont oil red (C. I. No.
• the other amount to be used is preferably 3 to 15 mass parts to 100 mass parts of the binder resin for a toner. Any of known charge control agents of nigrosine, quaternary ammonium salt or metal containing azo dyes can be properly selected and used.
• the amount to be used is usually 0.1 to 10 mass parts to 100 mass parts of a binder resin for a toner.
• a surface-treating agent added in the toner is present between the toner and a carrier or in the toner, whereby the powder fluidity and life of developing agent can be improved.
• the surface-treating agent there can be mentioned, for example, fine powders of colloidal silica, alumina, titanium oxide, polytetrafluoroethylene, polyvinylidene chloride, polymethyl methacrylate, polystyrene ultrafine particles and silicone.
• AEROSIL 130 As commercial products, there are mentioned, for example, AEROSIL 130, 200, 200V, 200CF, 200FAD, 300, 300CF, 380, R972, R972V, R972CF, R974, R976, RX200, R200, R202, R805, R812, R812S, TT600, MOX80, MOX170, COK84, titanium oxide T805 and titanium oxide P25 (these are products of Nippon Aerosil Co., Ltd.
• the specific surface area of the surface-treating agent is preferably 30 m 2 /g or more, particularly 50 to 400 m 2 /g as measured by nitrogen adsorption using the BET method.
• the amount of the surface-treating agent used is preferably 0.1 to 20 parts by weight per 100 parts by weight of the binder resin for a toner.
• the toner in the present invention may contain a polyolefin wax and the amount of the polyolefin wax used is 0 to 10 parts by weight per 100 parts by weight of the binder resin for a toner.
• the binder resin for a toner of the present invention colorant and, as necessary, other additives are sufficiently mixed using a powder mixer.
• the resulting mixture is then melt-kneaded using a heat roll, a kneader or a twin screw extruder to sufficiently mix the individual components.
• the melt-kneaded material is cooled, ground, and sieved to collect particles having particle diameters of ordinarily 5 to 20 micro-meters.
• the collected particles are coated with a surface-treating agent using a powder mixing method, to obtain a toner.
• the resulting toner according to the present invention can employ various development methods, for example, a cascade development method, a magnetic flash development method, a powder cloud development method, a touch-down development method, a so-called micro-toning development method using, as a carrier, a magnetic toner produced by grinding, and a so-called bipolar magnetic toner development method in which a required amount of toner charges are obtained by the friction between magnetic toner particles.
• the development methods are not restricted thereto.
• To the toner obtained by the present invention can be applied various fixing methods besides an oil-free fixing method, for example, an oil-coated heat roll fixing method, a flash fixing method, an oven fixing method, and a pressure fixing method.
• To the toner obtained by the present invention can be applied to various cleaning methods, for example, a so-called fur brush method, a blade method or the like.
• the molecular weight and molecular weight distribution of the binder resin for a toner are measured by GPC.
• the measurement is conducted in terms of the following conditions, based on the monodispersed standard polystyrene.
• the glass transition temperature (Tg) of the present invention was measured using DSC-20 (a product of Seiko Instruments Inc.) according to differential scanning calorimetry (DSC). About 10 mg of a sample was subjected to temperature elevation from ⁇ 20 to 100° C. at a rate of 10° C./min to obtain a curve; in the curve, an intersection between the base line and the inclined line of the endothermic peak was determined; the Tg of the sample was determined from the intersection. It is desired that, before the above temperature elevation measurement, the sample resin is heated to about 200° C., is kept at that temperature for 5 minutes, and is cooled quickly to normal temperature (25° C.), in order to allow the sample to unify a thermal history.
• DSC-20 a product of Seiko Instruments Inc.
• the ratio of THF insoluble component and THF soluble component of the present invention was obtained by the following measurement method.
• the acid value of the present invention refers to mg of potassium hydroxide necessary to neutralize 1 g of the resin.
• the OH value refers to mg of potassium hydroxide necessary to neutralize the acid anhydride necessary to esterify the OH group present in 1 g of the resin.
• G′ storage modulus
• the fixing properties of a toner were evaluated as follows.
• An unfixed image was formed using a copier produced by remodeling a commercial electrophotograph copier.
• This unfixed image was fixed using a hot roller fixing apparatus produced by remodeling of the fixing section of a commercial copier.
• the fixing was conducted at a fixing speed of the hot roll, of 300 mm/sec with the temperature of the heat roller being changed at intervals of 5° C.
• the fixed image obtained was rubbed 10 times by applying a load of 0.5 kg using a sand eraser (a product of Tombow Pencil Co., Ltd.), and the image densities before and after the rubbing test were measured using a Macbeth reflection densitometer.
• the hot roller fixing apparatus used had no silicone oil feeder.
• the development durability of a toner was evaluated by filling a toner in a commercial copier (a product of Toshiba Corporation, named Presio 5560), then conducting continuous copying of 100,000 copies, and evaluating the number of sheets fed from the start to the time when the deterioration of image density and image quality began.
• a commercial copier a product of Toshiba Corporation, named Presio 5560
• the production of a resin ⁇ -1 to a resin ⁇ -8 corresponding to the polyester resin (a-1) and a resin ⁇ -1 to ⁇ -11 corresponding to the polyester resin (a-2) is conducted.
• the production of a resin ⁇ -1 is described in concrete terms.
• the resin units and monomer compositions are changed to the conditions in Table 1 and Table 2 and others are the same as the method of the polyester resin ⁇ -1. Also, resin analytical results are shown in Table 1 and Table 2 along with those of ⁇ -1.
• a 5-liter, 4-necked flask was provided with a reflux condenser, a water-separating unit, a nitrogen gas inlet tube, a thermometer and a stirrer.
• a recycled PET flake weight-average molecular weight: 75,000
• Actcall KB300 a product of bisphenol A derivative by Mitsui Takeda Chemicals, Inc.
• dibutyl tin oxide was fed in an amount of 0.5 part by weight.
• resin ⁇ -1 30 parts by weight of resin ⁇ -1, 70 parts by weight of resin ⁇ -1, and 16.1 mole % of tolylene diisocyanate, based on the total moles of the polyhydric alcohol-derived structure unit in the resin ⁇ -1, were kneaded and reacted in a twin screw extruder at 180° C. to obtain resin 1.
• the resin had a Tg of 58.4C, a Mw/Mn of 17.7 as measured by GPC, and a peak molecular weight of 6,000.
• the resin also had a THF insoluble component of 9% by weight.
• a resin 100 parts by weight of a resin 1, 6 parts by weight of a carbon black (MA-100, a product of Mitsubishi Chemical Corporation) and 1.5 parts by weight of a charge control agent (BONTRON E-84, a product of Orient Chemical Instruments Inc.) and 2.0 parts by weight of a polypropylene wax (Hi-wax NP105; a product of Mitsui Chemicals, Inc.) were dispersed and mixed using a Henschel mixer; the resulting material was melt-kneaded at 120° C. using a twin screw extruder PCM-30 (a product of Ikegai Corporation) to obtain a toner composition in the bulk state. The resin after melt-kneading was coarsely ground using a hammer mill.
• a charge control agent BONTRON E-84, a product of Orient Chemical Instruments Inc.
• Hi-wax NP105 a product of Mitsui Chemicals, Inc.
• the coarsely ground resin was finely ground using a jet grinder (IDS 2, a product of Nippon Pneumatic Co., Ltd.), followed by air classification, to obtain a toner fine powder having an average particle diameter of 10 micro-meters (5 micro-meters or less: 3% by weight, 20 micro-meters or more: 2% by weight).
• a jet grinder IDS 2, a product of Nippon Pneumatic Co., Ltd.
• 100 parts by weight of the toner 100 parts by weight of the toner, 0.5 parts by weight of a hydrophobic silica (Aerosil R972, a product of Nippon Aerosil Co., Ltd.) was mixed using a Henschel mixer, feeding from the exterior to obtain toner particles.
• the toner particles were measured for offset resistance and development durability.
• Example 8 is described below. Examples 9 to 15 are conducted in the same manner as example 8 except for the conditions described in Table 4. The analytic results are also shown in Table 4. 30 parts by weight of resin ⁇ -7, 70 parts by weight of resin ⁇ -10, 3.0 parts by weight of a polypropylene wax (Hi-wax NP105; a product of Mitsui Chemicals, Inc.) as wax having a low-molecular weight, 2.1 parts by weight (8.7 mol % based on the total moles of all the polyhydric alcohol-derived structure units in resin ⁇ -7) of tolylene diisocyanate were melt-kneaded to obtain resin 13.
• a polypropylene wax Hi-wax NP105; a product of Mitsui Chemicals, Inc.
• the resin had a Tg of 58.1° C., a Mw (weight-average molecular weight)/Mn (number-average molecular weight) of 21.4 as measured by GPC, and a peak molecular weight of 6,000.
• the resin also had a THF insoluble component of 7% by weight. 100 parts by weight of a resin 7, 6 parts by weight of a carbon black (MA-100, a product of Mitsubishi Chemical Corporation) and 1.5 parts by weight of a charge control agent (BONTRON E-84, a product of Orient Chemical Instruments Inc.) were dispersed and mixed using a Henschel mixer the resulting material was melt-kneaded at 120° C.
• the toner composition was coarsely ground using a hammer mill.
• the coarsely ground resin was finely ground using a jet grinder (IDS 2, a product of Nippon Pneumatic Co., Ltd.), followed by air classification, to obtain a toner fine powder having an average particle diameter of 10 micro-meters (5 micro-meters or less: 3% by weight, 20 or more: 2% by weight).
• the durability of a toner was evaluated by conducting continuous copying of 100,000 copies in a commercial copier (a product of Toshiba Corporation, named Presio 5560), and then visually examining the surface of the fixing roller, and evaluating the deterioration or scrape on the surface of fixing films after printing out.
• a binder resin for a toner and a toner of the present invention comprises as described above; therefore, the resulting toner is superior in the fixing properties, offset resistance and development durability.
• the toner obtained according to the present invention can correspond to the recently increasing needs of copies and printers with a high speed and low-temperature fixing property.

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